Navigation Links
Weizmann Institute scientists show: How adversity dulls our perceptions
Date:5/11/2011

Adversity, we are told, heightens our senses, imprinting sights and sounds precisely in our memories. But new Weizmann Institute research, which appeared in Nature Neuroscience this week, suggests the exact opposite may be the case: Perceptions learned in an aversive context are not as sharp as those learned in other circumstances. The findings, which hint that this tendency is rooted in our species' evolution, may help to explain how post-traumatic stress syndrome and other anxiety disorders develop in some people.

To investigate learning in unfavorable situations, Dr. Rony Paz of the Institute's Neurobiology Department, together with his student Jennifer Resnik , had volunteers learn that some tones lead to an offensive outcome (e.g. a very bad odor), whereas other tones are followed by pleasant a outcome, or else by nothing. The volunteers were later tested for their perceptual thresholds that is, how well they were able to distinguish either the "bad" or "good" tones from other similar tones.

As expected from previous studies, in the neutral or positive conditions, the volunteers became better with practice at discriminating between tones. But surprisingly, when they found themselves exposed to a negative, possibly disturbing stimulus, their performance worsened.

The differences in learning were really very basic differences in perception. After learning that a stimulus is associated with highly unpleasant experience, the subjects could not distinguish it from other similar stimuli, even though they could do so beforehand, or in normal conditions. In other words, no matter how well they normally learned new things, the subjects receiving the "aversive reinforcement" experienced the two tones as the same.

Paz: "This likely made sense in our evolutionary past: If you've previously heard the sound of a lion attacking, your survival might depend on a similar noise sounding the same to you and pushing the same emotional buttons. Your instincts, then, will tell you to run, rather than to consider whether that sound was indeed identical to the growl of the lion from the other day."

Paz believes that this tendency might be stronger in people suffering from post-traumatic stress syndrome. As an example, he points to the 9-11 terror attacks in New York. Many of those who witnessed the strikes on the towers developed post-traumatic stress syndrome, which, for many of them, can be triggered by tall buildings. Intellectually, they may know the building before them bears little similarity to the destroyed towers, but on a more fundamental, instinctive level, they might perceive all tall buildings to be the same and thus associate them with terrifying destruction.

The scientific team is now investigating this idea in continuing research, in which they hope, among other things, to identify the areas in the brain that are involved in setting the different levels of perception. Paz: "We think this is a trick of the brain that evolved to help us cope with threats, but is now dysfunctional in many cases. Besides revealing this very basic aspect of our perception, we hope to shed light on the development of such anxiety disorders as post-traumatic stress syndrome."


'/>"/>

Contact: Yivsam Azgad
news@weizmann.ac.il
972-893-43856
Weizmann Institute of Science
Source:Eurekalert

Related medicine news :

1. Weizmann Institute scientists discover: Antioxidants cause fertility problems in females
2. Medical Training School, Pima Medical Institute Offering First Bachelor's Degree Program
3. Dana-Farber and Sanford-Burnham Institute license flu-targeting antibodies to Genentech and Roche
4. Laser Spine Institute Honored at the Gridiron Greats Night of Champions
5. Akron Institute of Herzing University Launches Its First Bachelors Degree Programs to Prepare Students for Even Greater Success in Business, Health Care and IT
6. Carpet and Rug Institute Expands Seal of Approval Program
7. San Diego State University and BIOCOM Institute Receive $4.95 Million Grant: The BRIDGE Project, Linking Education to Employment in San Diegos Life Sciences Industry
8. Northern California Cancer Center Changes Name to Cancer Prevention Institute of California
9. ChildCare Education Institute Supports the First Ladys Efforts to Reduce Childhood Obesity
10. GREENGUARD Environmental Institute Revamps Web Site
11. JBG to Develop Major Research Campus for National Cancer Institute
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/24/2017)... ... , ... With ProGlass Prism users now have the ability to simulate prism ... position, rotation, distortion, edge softness, edge blur, chromatic aberration, individual glass position offset, anchor ... Prism users are given the tools and effects to generate a fractal prismatic ...
(Date:2/24/2017)... ... February 24, 2017 , ... The Radiology Business Management Association ... programs at the annual Building Better Radiology Marketing Programs conference, held this ... Fort Worth, Texas. Nine awards are given out in five categories. They are:, ...
(Date:2/23/2017)... MA (PRWEB) , ... February 23, 2017 , ... ... and Department of Justice jointly issued a letter to withdraw previous ... accordance with their gender identity. The guidance issued in May 2016 by the ...
(Date:2/23/2017)... Los Angeles, CA (PRWEB) , ... February 23, 2017 , ... ... the first two episodes of WE TV’s “Mama June: From Not to Hot,” which ... of TV notable, “Mama” June Shannon, known to millions from the 2012 reality television ...
(Date:2/23/2017)... , ... February 23, 2017 , ... Dr. David Mahon ... Henderson, NV 89052. Dr. Mahon was named a 2017 Top Patient Rated Henderson ... is an online directory that recognizes local physicians and dentists who have earned high ...
Breaking Medicine News(10 mins):
(Date:2/23/2017)... MINNEAPOLIS , Feb. 23, 2017  Cogentix Medical, ... manufactures and markets innovative proprietary products for the urology ... and fiscal year ended December 31, 2016 before the ... The Company will host a conference call and ... on Thursday, March 9, 2017 at 11:00 a.m. Eastern ...
(Date:2/23/2017)... 23, 2017 Nevro Corp. (NYSE: NVRO), a global ... the treatment of chronic pain, today reported financial results for ... 2016 Accomplishment & Highlights: ... an increase of 228% as reported, over the prior year ... increase of 612% over the prior year ...
(Date:2/23/2017)... -- Im Rahmen seiner Schlüsselwachstumsstrategie arbeitet die ... chinesischen Provinz Guizhou, 2017 mit dem Angebot von Anreize schaffenden ... Entwicklung einer eingebetteten Hightech-Schlüsselindustrie. Foto - http://mma.prnewswire.com/media/471342/First_CRH__CHina_Railway_High_Speed__Train_Enters_Guian.jpg ... ... ...
Breaking Medicine Technology: